If 2011 was the year of the tablet, 2012 will be the year of the ultrabook.

Technology companies launched more than 100 tablet computers at last January’s International Consumer Electronics Show, and an estimated 56 million were sold worldwide throughout the year.

At CES 2012, which kicks off Tuesday in Las Vegas, at least 30 to 40 ultrabooks will be introduced, organizers say.

The ultra-thin, portable computers may replace two product lines in one fell swoop: netbooks and traditional laptops.

“If you look at the entire laptop or notebook category, what you’re looking at is really the end of that category as we know it, and everything migrates to an ultra-thin or ultrabook form-factor,” said Kurt Scherf, vice president and principal analyst for research firm Parks Associates.

The annual CES is billed as the world’s largest consumer technology trade show, attracting 149,000 attendees last year.

The four-day event will feature more than 2,700 exhibitors and 1.8 million square feet of exhibit space this year.

Many technological innovations have launched or caught fire at the show, such as VCRs, DVD players and high-definition TVs.

Ultrabooks feature a thin form-factor similar to tablets and netbooks but pack the computing muscle and full-size keyboards found on regular laptops.

Not necessarily new, ultrabooks are essentially Windows-based clones of Apple’s MacBook Air, a model that was released in 2008 and is less than 1-inch thick.

But much like what occurred with tablets — a market dominated by Apple’s iPad before last year’s CES — new versions from different manufacturers will mean far more variety and lower prices for consumers. Many will likely be powered by Microsoft’s forthcoming Windows 8 operating system and include instant-on solid state hard drives, which eliminate long initial boot times. Chipmaker Intel is the key player behind the ultrabook push.

This year’s show also will introduce consumers to perhaps the next breakthrough in television: not 3-D, but 4K.

“It’s a new screen resolution, and it is quite literally four times the pixels of 1080p,” said Jason Oxman, senior vice president of industry affairs for the Consumer Electronics Association, which produces CES.

Scherf said the 4K picture is “jaw-dropping gorgeous.”

But much like HD and 3-D before it, the super-high-resolution technology will face a slow rollout because it needs content to be produced in 4K format. 3-D TVs dominated CES a couple years ago but have failed to live up to the hype.

Microsoft is also making big waves at this year’s show, as chief executive Steve Ballmer’s pre-show keynote tonight will be the software giant’s last at CES.

“It’s the last year that Microsoft is going to keynote and have a full-fledged booth at the show,” Scherf said. “I think they want to go out on a high, meaning they’ve got a new direction for the OS — it’s not about the clunky old PCs anymore but it’s designed for a multiplatform environment.”

Microsoft said in a blog post that it would no longer have a keynote or booth at CES “because our product news milestones generally don’t align with the show’s January timing.”

A new element included in this year’s CES is Eureka Park, which will showcase about 100 technology startups.

“They’re all startups, entrepreneurs, new companies looking to make it big on the stage showing their next-generation products and hoping to get financing and retailers to buy their stuff,” Oxman said. “It’s a new, interesting area.”

Eureka Park’s presence at a show generally dominated by tech titans is a reflection of the nation’s growing focus on fostering entrepreneurship and innovation, a movement that includes initiatives such as President Barack Obama’s Startup America Partnership.

Boulder-based Modular Robotics will be among the companies exhibiting at Eureka Park, and the startup’s “cubelets” could be one of the top toys for kids this year.

“It’s a toy comprised of a bunch of 40 millimeter robotic cubes of magnetic connectors,” said Eric Schweikardt, design director for Modular Robotics. “They all do different things, and depending on how you snap them together, you can build robots without any wires, without any programming, without any of the traditional robot media that you might think about.”

There are three types of cubelets: action, sense and think. Stacking three together in one way will allow you push the blocks forward by moving your hand behind the stack without actually touching it. Restack them in another way and you can push the cubelets backward or have them rotate on their own.

“We’re trying to see how that’s going to change the way that kids play and the way that kids think about the world,” Schweikardt said.

What’s hot at CES

Ultrabook — Thin, lightweight and powerful laptops. They’re similar to Apple’s MacBook Air but are powered by Microsoft’s Windows operating system.

4K TVs — A new slate of super high-resolution televisions that deliver four times as many pixels as 1080p TVs. LG and Toshiba may unveil 4K sets.

Windows 8 — Microsoft’s latest operating system is expected to have a new user interface resembling the tile-based display of Windows Phone.

NFC — Near Field Communication technology can add even more power to smartphones and eliminate the need for items such as credit cards and physical keys. One project under development could allow a smartphone to wirelessly unlock doors that are fitted with digital locks.

Apple is donating $2 million to two human rights groups as part of CEO Tim Cook’s pledge to help lead the fight against the hate that fueled the violence in Virginia during a white-nationalist rally last weekend.

Five days after white nationalists and counterprotesters clashed in Charlottesville, more than $800,000 has poured into crowdfunding campaigns for the medical expenses of some of the victims, according to GoFundMe.